Oh hai! I’m Simone! You may remember me from such hits as, “Creating excruciatingly enormous tables of bugs I’ve reported in Apple products that Apple didn’t give a shit about” or “Trying to make sense of user interfaces that have gradually slipped into a morass of nonsense that Apple also doesn’t give a shit about”! Welcome back to your regularly-scheduled program! It’s only been about eight years, but I’m back on my bullshit, and here to complain about another Apple product!

Back in early November, a few days before the iPhone 12 mini (here-to-fore referred to as simply the “iPhone mini”) was available to order, Apple updated a support document, indicating that when charging via MagSafe (an annoying re-use of a previous term for a completely unrelated feature), the iPhone mini only charges at 12 W, despite the ability of other iPhone 12 models to charge at up to 15 W using the same MagSafe charger.

Well it got me wondering… maybe the limitation is not with wireless charging, but with charging the iPhone mini in general. Can you ever charge the iPhone mini with more than 12 W? The answer appears to be no, even with wired charging.

When I bought my iPhone mini, I wanted to make sure I could charge it as fast as possible, which meant getting Apple’s new 20W USB-C adapter. I can understand a bit why Apple stopped including chargers in the box with new iPhones, but it still smacks of nickel and diming. Luckily, I had recently received a $24 check from a settlement with Apple over them throttling older iPhones, like my iPhone SE which I had just replaced with the iPhone mini. So I basically got a free charger… just like I did last time!

But to know how much power the iPhone mini was actually drawing would be difficult, as I didn’t have a multimeter in my house to test. Luckily, iOS keeps track of voltage, amperage, and battery level (for diagnostics and probably to power *ba dum psh* part of the battery charge graphs in Settings). Here’s how to access these logs.

1. First, we need to make it easy to get the volt/amp logs. Go to Settings —> Accessibility —> Touch —> AssistiveTouch, and turn that on.
2. Then, tap “Customize Top Level Menu”, tap on any of the icons, tap “Analytics”, and then tap “Done”. Now you have a little floating home button on your screen (handy for home button-less iPhones!) that you can press and then get analytics with one touch!
3. Now, do all the battery-related things you want to log. Plug your iPhone in to various chargers, unplug it, let the charge drain, etc. The logs take snapshots at about 5 minute intervals, so you’ll probably want to keep things the same for about 20-25 minute chunks of time so you get a couple data points during each battery activity.
4. When you’re ready to get the log data, press the AssistiveTouch button, and then tap the Analytics icon. You’ll get a banner across the top of the screen letting you know that gathering analytics has started.
5. Wait a minute or two. You should receive another banner across the top of the screen letting you know when iOS has finished collecting analytics.
6. Now, go to Settings —> Privacy —> Analytics & Improvements —> Analytics Data, and scroll down to “sysdiagnose…” in the list. You should see an entry with a date and timestamp when the analytics finished.
7. Tap on the sysdiagnose you’re interested in. You should see a blank screen.
8. Tap the share button in the upper-right corner of the screen. AirDrop the sysdiagnose file to your computer. It’s usually a couple hundred megabytes in size, but it transfers via AirDrop in only a few seconds.
9. Now, on your Mac, unzip the sysdiagnose .zip file. Inside, navigate to logs —> BatteryBDC, and find the most recent “BDC_SBC_version1.2….csv” file (there will probably be several with many different timestamps). Open this file.

The .csv file you’ve just opened is a table monitoring the state of the battery. You’ll see columns for TimeStamp (in GMT), CurrentCapacity (a numerical value from 0-100 representing how fully charged the battery is), IsCharging (0 = not charging, 1 = charging), Amperage (in milliamps), Voltage (in millivolts), as well as a couple other columns (I’m not sure what PresentDOD0 and InstantAmperage mean, and I’m not sure what units the temperature is measured in).

Here’s my BatteryBDC table under a number of different scenarios. I tested charging the iPhone mini when connected to 1) Apple’s new 20W fast charger, 2) connected to an old 12W power adapter, and 3) to my Tresanti standing desk that I got from Costco, which has 2.4 amp charging ports. (It’s not quite this model, but it’s close enough.) Each scenario is tested when the iPhone mini’s battery level is under 50% and when it’s over 50%. I also caught how much my 2015 MacBook Pro will charge the iPhone mini when it’s already charged above 80%.

As you can see, when charging via Apple’s new 20W charger, the fastest wattage delivered was 11.5W, well below the 20W rating. Above 50% charge, it reduces to 9.0W while charging. In 22 minutes, I was able to charge about 37% of the battery at the fastest point.

Via the old 12W iPad charger, I got a maximum power delivery of 9.4W. There wasn’t as steep of a drop-off above the 50% charging level; it seemed to gradually taper off as the battery level approached 100%. In 22 minutes, I was able to charge about 34% of the battery.

Via my Tresanti standing desk, I got a maximum power delivery of 9.4W as well. In 20 minutes, I was able to charge about 32% of the battery.

Via my 2015 MacBook Pro, I got a maximum power delivery of 3.5W, but I was only testing above 80% charge so it might charge faster when the battery is more drained.

As you can see, this answers a key question for new iPhone mini owners. Is the new 20W charger worth it? The answer is a resounding no, unless you have no other way to charge your iPhone.